As is generally known, industrial robots have been used for attaching a workpiece to and removing a workpiece from machine tools. Industrial robots for such purposes include a gantry robot provided with a workpiece feed means spanning over a machine tool, a loading robot designed specially for a machine tool, and a general purpose articulated robot provided with robot arms having a plurality of degrees of freedom of motion, a robot wrist, and a robot hand.
The functional robot mechanism of the gantry robot, in general, has a large construction, and is not necessarily suitable for use in combination with a lathe. The loading robot is designed specially for a specific machine tool, and is unable to be applied generally to a desired machine tool. Teaching the articulated robot a series of robot actions, including feeding a workpiece and transporting the same, requires a complicated teaching procedure because the articulated robot has many axes about which the component parts operate, and it is difficult to install the articulated robot in combination with a machine tool. Thus the articulated robot is not satisfactory in this application.